Method of making scrapless laminations for producing a plurality of units



Aug. 19,, 1969 a. B. MICHIULIS 3,461,758

METHOD OF MAKING SCRAPLBSS LAMINATIONS FOR PRODUCING A PLURALITY OF UNITS Filed Jan. 16, 1967 2 Sheets-Sheet l 15 I J I /1 F562 F|G.5

INVENTOR Bxwvo BJVIOIIIULIS BY 714,8 MW

ATTORNEY;

Aug. 19, 1969 B. MICHIULIS 3,461,758

METHOD OF MAKING SCRAPLESS LAMINATIONS FOR PRODUCING A PLURALITY 0F uums Filed Jan. 16, 1967 2 Sheets-$heet 2 BY Mamv A'r'ronuzvj United States Patent 3,461,758 METHOD OF MAKING SCRAPLESS LAMINATIONS FQR PRODUCING A PLURALITY 0F UNITS Bruno l3. Michiulis, Wood Dale, Ill., assignor to Sola Basic Industries, Inc, Milwaukee, Wis. Filed .Ian. 16, 1967, Ser. No. 609,656 lint. Cl. 1626f 1/02; Hillf 7/06 US. Cl. 83-32 7 Claims ABSTRACT OF THE DISCLOSURE A method of producing various shape portions of core laminations with a minimum of scrap and which can be interchangeably assembled into various types and configurations of core structures.

This invention relates to laminated or stacked core structures for electrial induction apparatus such as constant voltage and current devices, transformers, reactors, magnetic amplifiers, and the like. More particularly, the invention relates to a method for the substantially scrapless stamping from a thin sheet or strip of magnetic material of a plurality of laminations or core components having a plurality of different shapes or configurations for building up a plurality of different core structures which can be made from a relatively simple die arrangement.

It is well known in the electrical induction art to build up the magnetic core structures for transformers, reactors, magnetic amplifiers, and the like from laminations or components having various shapes or forms such as the I shape, the E shape, the L shape, and the T shape. It is also well known to stamp a plurality of such laminations from a sheet or strip of magnetic material in a single operation. In general, however, and especially in the so-called scrapless type of operation, such stampings are suitable for producing only a single core structure for a particular type or design of transformer, reactor, or the like. They are not adapted for interchangeable use in forming core structures of different types and configurations for various types of induction apparatus.

A principal object of the present invention is to provide for the economical and substantially scrapless stamping or punching from a single sheet or strip of magnetic material of laminations having a plurality of different shapes or configurations adapted for use in constructing 'various types of magnetic core structures.

A further object of the invention is to provide for the economical production of multi-shaped laminations adapted for interchangeable use in constructing core structures of different configurations.

A still further object of the invention is to provide for the substantially scrapless production of multi-shaped laminations adapted for use in constructing shell-type core structures having windows of different sizes and disposition.

Another object of the invention is the provision of multi-shaped laminations adapted for use in core structures having differently arranged magnetic shunts.

Still another object of the invention is to provide for the more economical production of different core structures for various types of power induction apparatus, particularly with respect to apparatus produced by a particular manufacturer.

In one aspect of the invention, provision is made for punching or stamping one long E member or component, one double or reverse E member (sometimes hereinafter referred to as EE), two short E members, one I member, and two shunts from a thin sheet or strip of magnetic material to provide a plurality of multi-shaped laminations, the arrangement being such that there is 'very little 3,461,758 Patented Aug. 19, 1969 waste of the magnetic material and results in a substantially scrapless operation. These laminations may be interchangeably used to construct, for example, a shell-type core having a center leg and windows of a predetermined size on each side, a similar structure having more elongated windows on each side, and a similar structure utilizing an EB core member to provide a core structure having two or more shunts.

In a second aspect of the invention, two I shaped laminations may be stamped without additional waste to form the components of two complete types of core structures.

In a third aspect of the invention, one or both of the E members may be separated into two L and one I members.

The foregoing and other aspects, objects, features and advantages of the invention will become apparent from the following description taken in conjunction with the acompanying drawings which illustrate exemplary embodiments of the invention.

In the drawings:

FIG. 1 illustrates a strip of magnetic material having a plurality of multi-shaped core laminations arranged thereon in accordance with the present invention;

FIG. 2 illustrates one type of core structure utilizing the laminations of FIG. 1; and

FIGS. 3-5 illustrate other types or configurations of core structures interchangeably utilizing the laminations of FIG. 1.

Referring to FIG. 1, there is shown a strip 10 of thin magnetic material adapted to be die stamped or punched to provide a plurality of laminations for building up the cores of electrical induction or magnetic apparatus. In accordance with the present invention, the lamination pieces are of a plurality of different shapes or configurations adapted for interchangeable use in core structures of different types of induction apparatus. There is thus shown an E lamination or core component 12 having elongated side legs 14 and 16, a center leg 18, and a base portion 20. In opposed relationship thereto is a reverse or EE lamination 22 having elongated legs 24, 26 and 28, a base section 30, and short legs 32, 34 and 36. Nestled between the elongated legs of the opposed E and EE laminations are a pair of E laminations 38 and 40 having short legs 42, 44 and 46. Arranged adjacent the base 30 of lamination 22 and at the ends of legs 32, 34 and 36 are one or more I laminations 48 and 50, the lamination 4 8 being shown in full lines and the lamination 50 in dashed lines. interposed between the legs 32, 34 and 36 of EB lamination 22 are two magnetic shunt elements 52 and 54. Similar shunts 52A and 54A (shown in dashed lines) may also be provided in the base 20 of lamination 12 to provide a second EE component and additional shunts if desired. The entire waste is limited to the cut-outs 56 around the short legs of E laminations 38 and 40 and the cut-out 58 around leg 34 of EB component 22 and the shunt element 54. Further diversification also can be obtained by separating the E member 12 into an I and two L sections as indicated by the dashed lines 60.

The length of the shortened E members 38 and 40 is the same as the width of the elongated E member 12 and the EB member 22, the center legs 18, 26 and 44 all have the same or equal widths, and the spaces between all of the legs, both short and elongated, are the same or equal so that the respective legs will match up when assembled into core structures as illustrated in FIGS. 2 to 5 and hereinafter described. Likewise the I members 48 and 50 have a length equal to the width of the several E and EE members. It will also be evident that one or more I members 48 could be arranged adjacent the E member 12 instead of EB member 22, or additional I members could be so arranged.

As an example, a single die arrangement can be used with removable inserts for portions 52A, 54A and 56 so as to produce selectively the parts needed. In this manner, the die cost will be kept at a minimum.

The utilization of the various multi-shaped laminations or core components produced by the punching or stamping operation of FIG. 1 to build up various core structures is illustrated in FIGS. 2 to 5. In FIG. 2, for example, which could be used in a constant voltage device such as shown in U.S. Patent No. 2,143,745, laminations 12 and 48 are combined for one type of core structure. In FIG. 3, laminations 12 and 3 8 or 40 are utilized. In FIG. 4, which could be used with devices such as illustrated in U.S. Patent No. 2,694,177, laminations 22, 38 or 40, and 48 are used. FIG. illustrates one application of the shunt elements 52 and 54.

Magnetic shunts can be used as needed in FIGS. 2, 3 and 4.

As a further advantage, structures, such as shown in FIG. 2, can have legs 14, 16 made to be of a width greater than one-half the width of middle leg 18 as in U.S. Patent No. 2,806,199 and the width of base 20 made greater than one-half the width of leg 18. This is of particular value when the material used to make the laminations is grain oriented. When it is grain oriented, the magnetic properties of such a steel in the cross-grain direction are inferior to those in the with-grain. Thus, the base must be wider for most efficient operation. The desired width can thus be obtained with an optimum scrapless operation.

Other combinations of these laminations or core components to produce a core structure will also be apparent, and it is intended not to be limited by the core structures disclosed but only by the scope of the appended claims. It will also be understood that suitable dies, well known in the art, are provided for the punching or stamping operation.

What is claimed is:

1. The method of producing a plurality of differently shaped magnetic core laminations from a sheet or strip of magnetic material for interchangeable use in forming bers, at least one of said elongated E members being provided with reversely extending legs having rectangular- 1y shaped shunt elements arranged.

2. The method as set forth in claim 1 in which said sheet has at least one I member arranged thereon, said I member extending transversely of said sheet adjacent an elongated E member and having a length equal to the width of said elongated E members.

3. The method as set forth in claim 1 in which said shunt elements have a length slightly less than the width of the spaces between said reversely extending legs, and the center reversely extending leg has a length slightly less than that of the outer legs thereby to provide air gap spaces in an assembled core structure.

4. The method as set forth in claim 1 in which said short legged E members have a width equal to the width of said elongated E members, all of the center legs of the E members have the same width, and the spaces between the legs of all of the E members are equal.

5. The method as set forth in claim 1 in which at least one of said elongated E members is divided into an I and two L members.

6. The method as set forth in claim 1 wherein a single die provides for punching said sheet, said die having removable inserts for punching the spaces between the legs of said short legged E members.

7. The method as set forth in claim 6 wherein said die has removable inserts for punching the spaces between said reversely extending legs and the shunt members contained therein.

References Cited UNITED STATES PATENTS 509,770 11/1893 Scott 29-15561 X 1,877,254 9/1932 Ritter. 2,892,249 6/1959 Feinberg et al. 336 X 2,934,727 4/1960 Cornell 336-465 X 3,316,621 5/1967 Schwarz et al. 29155.61

FOREIGN PATENTS 788,222 Great Britain.

JOHN F. CAMPBELL, Primary Examiner C. E. HALL, Assistant Examiner U.S. Cl. X.R.

zg gg UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,L;6l,758 Dated Augggt l9, 199

Inventorfisc) Bruno B. Michiulis It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

' Column 1, line 19, "electrial" should be --e1ectrical--; Column 11,, line 3, insert "therebetween" after "arranged" SlGNED ANU SEALED ocrzam (SEAL) Attest:

Edward M. Fletcher. Er. mm E- 'SGHUYLER, JR Anesting offieer fimissioner of Patents 

